Re: NetBSD hardclock overhead growth

["Michael L. Hitch" <mhitch%NetBSD.org@localhost>]

On Mon, 17 Aug 2015, Johnny Billquist wrote:

> On 2015-08-16 21:33, John Klos wrote:
> > > Not an 11/780, but anyway...
> > > Krille:/usr/src# uname -a
> > > NetBSD Krille.Update.UU.SE 5.99.44 NetBSD 5.99.44 (Krille) #387: Mon
> > > Jan 24 18:15:12 CET 2011
> > > root%GW.SoftJAR.SE@localhost:/usr/obj/sys/arch/vax/compile/Krille vax
> > > Krille:/usr/src# sysctl -a | grep hw
> > > hw.machine = vax
> > > hw.model = VAX 8650
> >
> > What results do you get for your machine? The VLC and 8650 are supposed
> > to be about the same speed, but the 8650 has twice the cache...
>
> With the binary you sent, and 100.000 iterations:
>
> Microseconds for one run through Dhrystone:  103.6
> Dhrystones per Second:                      9652.5

  Ok, this is very strange.  I dug out one of my VLC systems and running 
the 5.1 pkgsrc version of dhrystone gives me:

Microseconds for one run through Dhrystone:   89.9
Dhrystones per Second:                      11123.5

8.8u 0.1s 0:10.89 82.4% 0+0k 0+0io 0pf+0w
# sysctl hw.model
hw.model = VAXstation 4000 VLC
# uname -v
NetBSD 7.99.19 (GENERIC) #0: Sun Aug 23 14:45:02 MDT 2015 
mhitch@nuc.hitch:/home/mhitch/NetBSD-current/OBJ/vax/home/mhitch/NetBSD-current/src/sys/arch/vax/compile/GENERIC

  I don't know why John gets such poor results.

  I wonder if the ROM version would make any difference, if there is some 
difference in how the system is initialized before booting.

  This is from the VLC I ran the above on:

KA48-A V1.2-32B-V4.0
08-00-2B-23-02-4B
24MB


Mike

---
Michael L. Hitch                        mhitch%montana.edu@localhost
Operations Consulting,  Information Technology Center
Montana State University, Bozeman, MT     USA